Manufacture of antimony colors.



' earthy sulfo antimoniates or sulfo ar-- "LEON BRUNET, or BRIOUD-E,FRANCE.

MANUFACTURE OF ANTIMONY COLORS- Specification of Letters Patent.

' Patented June 25,1907.

Application filed August 22, 1905. Serial No. 275,297.

To all whom it vita/'11) concern:

Be it known that I, LiioN BRUNEna citizen of the Republic of France, anda resident of Brioude, Rue St. Pierre, in the Republic of France,chemist, have invented certain new and useful Improvements in theManufacture of Antimony and Arsenic Colors, for which application hasbeen made in France, April 15, 1905; Germany, June 27, 1905; Austria,July 10, 1905; Belgium, July 8, Spain, July 12, 1905; Italy, July 25,

This invention relates to improvements in the manufacture of antimonyand arsenic colors, such as white antimony colors or antimony ceruse,andyellow and red sulfid of antimony.

All the processes hitherto known and employed for the manufacture ofsulfids of antimony and arsenic, also called antimony vermilion, arebased on the following principles. Decomposition of the alkaline, oralkaline seniates by hydrochloric or sulfuric acids:

2SbS Na +3SO H =3SO Na +3H S+Sb S Sb S Ba -i-3SO H =3SO Ba+3H S+Sb S SbS Ca +6HGl=3GaCl +3H S+Sb S 2ASs,i 1a,+3s0,11,=3so,1 m,+311,s+As,s It isevident that in all these reactions there is an excessive yield ofsulfidric acid whichis a great drawback and further the solutions of theresidual products, sulfates or chlorids of sodium or calcium, areindustrially worthless. .In addition to this the necessary acids forthis manufacture have to be purchased. For'vermilion of antimony, theyposulfites of sodium or calcium are separated-which aretreated withchlorid or sulfate of antimony, adding five or six times the hyposulfitetheoretically necessary, the price of which is high. It will be noticedthatin.

these processes the cost of manufacture is very high, and it is evidentthat for this reason t ere has not been a regular demand for thesecolors as pigments for painting, in spite of their remarkable wearingualities and covering power, and they are so d more particularly forvulcanizing and coloring india-rubber which is an industry which can payhigh prices.

The present invention has for its object a process of manufacturingthese antimon and arsemc colors by the precipitation of a kaline oralkaline earth sulfo antimoniates and sulfo-arseniates by means of thegas I given off from roasting any suitable metallic sulfids producingsulfurous anhydrid, and more particularly the roasting of antimony ore.

I will now describe particularly the steps by which those versed in theart may carry out the process: The pyrites are roasted as usual, but thegasessulfurous acid and excess of air, smoke, and soot,*after beingpassed into a chamber where the smoke (or soot) is deposited, are drawnforward by a strong draft created by afan. They then pass between thearms of this fan, and the saline solution, such for instance, as.sulfoantimoniate of barium (it would be the same thing withsulfoarseniate of barium) is introduced through the hollow trunnions ofthis apparatus. The sulfo-antimoniate of barium thus penetrates by thetrunnions and owing to centrifugal force passes along channels formed'in' the wings of the fan. The liquid is projected in the form of rain,almost like dust, which mixes with the sulfurous anhydrid hichrpassesthrough the wings.

At this moment, the reaction is produced and it always takes place, asseen, in an acid medium. This very important condition is the cause ofthe success of the operation. The reaction is as follows:,Sulfo-antimoniate of barium added to sulfurous acid added to air,produce hy osulfite of barium added to yellow sulfite o antimony. Theformula Fromvthis equation it will be seen that no H 8 is given oif. Theprecipitate is. .absolutely pure. The spray pro'ect'ed by the fan fallson the floor of the chain or from thence it passes into a basin where ittests and the ye ow precipitate separates-itself from the 1sulfo-antimoniate or sulfo-arseniate is. treated, thevscope of myinvention evidentlyineludes both.

The solutions of the sulfo-antimoniate are concentrated, the percentageevidently depending on the solubility of each, as known 2. The processof manufacturingnntiinony coloring matters which consists in the pre- 15 cipitation of a solution of sulfo-antimoniate of the alkaline earthbases, by the action of sulfurous acid.

In Witness whereof, I have hereunto signed my name this 8th day ofAugust 1905, in the 20 presence of two subscribing Witnesses.

LEON BRUNET.

Witnesses: ANTONNI MONTEILTRET,

HANSON 0. Colin.

